Existing frames for prosthetic heart valves typically comprise rows of angled struts and a plurality of axial frame members spaced apart around the circumference of the frame. The plurality of axial frame members may comprise a plurality of leaflet attachment members (for attaching to the commissures of the supported valvular structure) and a multitude of axially directed struts extending between the rows of angled struts. A frame usually has three or more axially directed struts for every leaflet attachment member, and generally has no more than two angled struts located in between adjacent struts or other axial frame members. Indeed, having a large number of axially directed struts is perceived to be necessary for preserving the structural stability of the stent and/or valve. Unfortunately, having a large number of axial struts can come at the expense of valve flexibility.
A need therefore exists for stents and prosthetic valves that can have a high degree of flexibility, without compromising mechanical integrity or function.